Mayor Eduardo Paes confirmed the city’s action with the goal of halting the disease, transmitted by mosquitoes and potentially fatal.

The onset of Carnival, beginning Friday, coincides with a significant rise in dengue cases, spurring a vaccination campaign. With over 11,000 cases this year, Rio has already seen record hospitalizations for dengue in January.

Amid this surge, Brazil has reported almost 365,000 dengue cases nationwide this year, a fourfold increase over the same time last year, with 40 deaths recorded.

To combat the epidemic, Rio will establish 10 treatment centers, and an emergency coordination center has been created. Dengue emergencies have been declared in two other regions, including Minas Gerais and the Federal District.

Brazilian Health Minister Nísia Trindade highlighted the crisis, exacerbated by high temperatures and rainfall that favor mosquito breeding, urging nationwide preventive action.

The Aedes aegypti mosquito spreads not only dengue but also Zika, chikungunya, and yellow fever. While most infected people are symptom-free, the virus can lead to hospitalization or death in severe cases.

Brazil has initiated dengue vaccination with the Qdenga vaccine, targeting 3.2 million citizens in 2024, prioritizing 10-14-year-olds. The ministry plans to increase vaccine production and availability.

Rio will soon start vaccinating children, with clinical trials showing the vaccine substantially reduces severe dengue risk. According to WHO Director-General Tedros Adhanom Ghebreyesus, a global dengue spike, partly driven by El Niño, has led to over 5 million cases worldwide, with Brazil accounting for a significant portion.

The growing prevalence of dengue, intensified by climate change, warns of expanding vector-borne diseases and their impact on human health.